If you operate multiple sites and use the same editors and writers for these sites, you can connect your Kapost instance to multiple CMS's.
Select App Center from the Settings area of the side navigation bar. Scroll down and select Install More Apps.
Select the CMS Category, then click on the appropriate CMS.
Select your instance from the drop-down menu then click install. Enter the necessary information then click Connect. This article lists all the CMS's and how to connect.
Follow the same steps to connect another CMS.
If you use WordPress MU, then you should add each subdomain as a site. For instance, if you have SiteA.myWP.com and SiteB.myWP.com in the same WordPress instance, you should add SiteA.myWP.com as one site and then click to add SiteB.myWP.com as a second.
Once you have your site or multiple sites connected, you can then synchronize your categories or go straight to publishing posts from Kapost to your CMS.